Multifiber optical connectors provide high performance, single mode transmission of light beams through optical fibers, sometimes referred to as "waveguides", in optical fiber arrays found in the connectors. See, for example, U.S. Pat. No. 5,214,730, Nagasawa et al. Multifiber optical connectors such as those disclosed in the Nagasawa et al. and other patents generally are formed by a pair of multifiber optical connector plugs having spring members for pressing the multifiber optical connector plugs toward each other in an axial direction. Guide pins for aligning the multifiber optical connector plugs are provided in an attempt to hold the ends of the individual fibers in the fiber-optic arrays against one another in registration so as to ensure a good optical interface between the arrays, and therefore acceptable data transmission through the connector.
Generally, the connectors also comprise housings or "ferrules" which are adapted to hold the optical fibers in the connector in a fashion so as to secure registration of the two fiber-optic arrays found in the individual halves of the connectors. See, for example, U.S. Pat. No. 4,753,515 Sato et al. In order to secure the individual waveguides of the arrays in the ferrules, the waveguides are typically secured in the ferrules in "C-shaped" channel members. See Sato et al., column 2, lines 46-53. The fiber-optic array is further secured in the C-shaped channel by providing a bonding agent to the C-shaped channel and the array, thereby gluing the array into the ferrule. See Sato et al., column 3, lines 9-16.
Many arrangements have been proposed in the art for forming grooves in ferrules to hold individual fibers of a fiber-optic array therein. Conventionally, the grooves can be simply machined in the ferrules by standard mechanical machining techniques. Alternatively, it has been suggested to "etch" grooves in the ferrule, thereby creating V-shaped grooves to hold the fibers. See, for example, U.S. Pat. No. 4,657,341, Sammueller, column 3, lines 17-23. When etching is employed as described in the Sammueller patent, the ferrule must be made of an etchable material such as silicon, in order for the V-shaped grooves to be formed therein.
In the mechanical technique, etching technique, and other groove-forming techniques employed in the art, grooves are produced which unfortunately cannot consistently hold the individual fibers in registration in the ferrule, and so the individual waveguides tend to be only loosely registered in the grooves. Therefore, the individual waveguides can slightly move when the two halves of the connector are placed together, or when the connector is subject to movement from outside forces during use.
The prior multifiber optical connectors thus have the disadvantageous characteristic of misalignment of the fiber-optic arrays which must normally be closely joined together in order for optical data to be transmitted through the connector with speed and accuracy. The aforementioned connectors do not efficiently interface the waveguides in the separate connector halves since the ferrules found in these connectors are simply not machined with enough accuracy to ensure a reliable optical interface at the fiber-optic arrays at all times during the connectors' use. Furthermore, prior connectors and ferrules do not provide accurately machined grooves to house the individual fibers so as to ensure good mechanical registration of the fibers within the ferrules. This results in a generally unreliable connector which introduces a high probability of data error when optical information is bussed through the connector.
There therefore exists a long-felt need in the art for fiber-optic connectors which ensure consistent, high quality data communication. This long-felt need extends to fiber-optic connectors having ferrules which can be machined with high precision and accuracy in the submicron range to hold the individual fibers of the fiber-optic array in registration in the ferrules. There further exists a long-felt need in the art for techniques to machine ferrules for use in connectors having fiber-optic arrays which will ensure that the fiber-optic arrays can be both simply registered in the ferrules, and held in precise alignment with other fiber-optic arrays in the connector. Such results have not heretofore been achieved in the art.